Additive manufacturing and rheological characterization of ceramic matrix composite inks with high fiber volume loadings

Abstract

Additive manufacturing of fiber-filled ceramic matrix composites (CMCs) can be used to tune local properties via controlled fiber orientation. Increasing the loading of fibers in additively manufactured CMCs is needed to improve the fracture toughness, yet printing CMCs with high fiber loadings (> 20 vol%) remains challenging. In this work, the combination of viscous silicon oxycarbide preceramic resins, short carbon fibers (50 µm × 7 µm), and Vibration-Assisted Printing enable printing of a mixture with 39.4-vol.% carbon fiber (total loading of 43.3 vol%) with omnidirectional fibers within the bead.